 
 (defn part
   "Generate version of the model using the variations fns."
-  [model & variations]
-  ((apply juxt identity variations) model))
+  [instrument model & variations]
+  (->>
+    model
+    ((apply juxt identity variations))
+    (map (partial all :part instrument))))
 
 (defn introduce-after
   "Gradually introduce each part after t beats."

      (pan2 pan)
      (* vol)))

(defmethod live/play-note :default [{:keys [pitch pan]}]
  (when pitch (horn :freq pitch :pan (or pan 0))))

    (map pan)
    (where :pitch (comp midi->hz A central-african-scale))
    (tempo (bpm 120))
    live/play))



